Method and means for using low-compression fuels



ill

Jill

fuel.

Patented Mar. 2, 1926.

UNITED STATES PATENT OFFICE."

THOMAS MIDGLEY, 33., Of DAYTON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

GENERAL MOTORS CORPORATION, OF

DELAWARE.

DETROIT, MICHIGAN, a

GQRPORATION 01 METHOD AND MEANS FOR USING LOW-COMPRESSION FUELS.

No Drawing.

pressure. The principal object ofthis in-.

vention is to employ selenium compounds to suppress the fuel knock.

This application is a continuation in part of my copending application Serial No. 553,270, filed April 15, 1922;

Kerosene has a critical compression pressure of-about pounds. The critical compression pressure of gasoline varies from about pounds for the commoner forms now marketed to about 125 pounds for aviation gasoline employed in airplane engines. These fuels are termed low'compression fuels. When the vapors of any one of them is mixed withair, compressed to a compression pressure in excess of the normal critical compression pressure of the fuel, and burned, as in an internal-combustion engine, a fuelknock' is produced.

I have found that vapors of selenium compounds added to the fuel-air mixture suppress this fuel knock and permit an in.- crease in the engine compression pressure with a normal burning characteristic of the By way of an example of one method of carryin H out myinvention, I dissolve 17 c. *c. o diethyl selenide' Se(C H in 1 gal on of gasoline having a normal critical compression pressure of about 75 )ounds. This solution 'or high compression uel is fed through a carburetor into the cylinder of an internal-combustion engine Application filed September 18, 1923. Serial No. 663,494.

having a'compression pressure of about 100 pounds, the solution being vaporized and mixed with a1r as 1s common practlce 111 engine operation. The gaseoushigh compression fuel is ignited and the engine 0perated without a fuel knock. The gasoline forms the fuel base and the selenium com pound increases the critical compression pressure of this base.

This process may be varied-by changing the proportions according .to the increase in critical compression pressure desiredand by using other selenium compounds in place of the diethyl selenide' Among. the compounds which I have successfully employed are other alkyl compounds including dipropyl selenide, and diphenyl selenide, selenilm oxychloride and selenium tetra chlor1 e.

I prefer to employ the selenium compounds Whichare soluble in the fuel to promote t'-e mixing of the two. The compound may be added to the fuel-air mixture just before the latter is burned. Blending agents may be employed if the selenium compound does not dissolve readily in the fuel.

I claim: u 1 A composition of matter comprising a low compression fuel; and a volatile selenium compound incorporated therein and adapt-- ed to inoreasethe critical compression pressure of the'f'uel.

2. A composition of matter comprising a,

THOMAS MIDGLE-Y, JR- 

